A Lactobacillus plantarum CZ25 for promoting the growth of pickled vegetables, microbial agent, preparation method thereof and application

Abstract

The present invention relates to the field of microbial technology, and specifically discloses a Lactobacillus plantarum CZ25 for promoting the growth of pickled vegetables, a bacterial agent, a preparation method of the bacterial agent and its application. It was deposited with the China General Microbiological Culture Collection Center on September 18, 2024, and its deposit number is: CGMCC NO. 31988. Lactobacillus plantarum CZ25 has the DNA sequence of SEQ ID NO. 1 in the sequence listing; Lactobacillus plantarum CZ25 has the effect of inhibiting harmful bacteria, and its fermentation broth has the characteristic of inhibiting the growth of harmful microorganisms, can regulate the hurdle factors, and the pH value of the lactic acid solution is 3.34 - 3.41. Lactobacillus plantarum CZ25 can survive and reproduce in an environment with a relatively low pH value, has good acid resistance and a high survival amount.

Description

Technical Field

[0001] The present invention relates to the field of microbial technology, and particularly relates to a Lactobacillus plantarum CZ25 for promoting the growth of pickled vegetables, a microbial agent, a preparation method thereof, and an application thereof. Background Art

[0002] In the process of food processing and preservation, sterilization and antibacterial are key steps to ensure food safety and extend the shelf life of food. At present, the commonly used sterilization and antibacterial methods in the food industry mainly include sterilization at normal temperature, pasteurization, high-temperature sterilization, adding preservatives, etc. To further enhance the preservation effect of food, a small amount of additives such as preservatives and antioxidants is usually added during or after the sterilization process; sterilization at normal temperature usually refers to the sterilization treatment carried out at room temperature, mainly relying on physical methods (such as ultraviolet rays, filtration) or chemical methods (such as preservatives); the sterilization conditions for pasteurization are 61-63°C for 30 minutes, or 72-75°C for 10-15 minutes. Such conditions can kill some pathogenic bacteria but cannot completely eliminate them, and preservatives (such as potassium sorbate, sodium benzoate, etc.) are usually added; high-temperature sterilization usually refers to the sterilization treatment carried out at a temperature of 121°C, which is sufficient to kill most bacteria, molds, and yeasts, including spores.

[0003] However, high-temperature sterilization will cause a decline in the taste, color, and nutritional value of food, especially for heat-sensitive vitamins and proteins; pasteurization and sterilization at normal temperature cannot kill most bacteria, molds, and yeasts, there are certain food safety risks, and a large amount of preservatives need to be used, and long-term intake may have an adverse impact on health.

[0004] Therefore, how to ensure food safety and food quality while achieving sterilization and antibacterial is an important problem faced by the food industry. At present, no perfect solution to the above problems has been found. Summary of the Invention

[0005] The problem to be solved by the present invention is to provide a Lactobacillus plantarum CZ25 for promoting the growth of pickled vegetables, a microbial agent, a preparation method thereof, and an application thereof, and to verify the application and effect of this strain in food production.

[0006] To achieve the above object, the present invention provides the following technical solution: A Lactobacillus plantarum ( Levilactobacillus suantsaii ) CZ25, characterized in that: the Lactobacillus plantarum ( Levilactobacillus suantsaii ) CZ25 is deposited in the China General Microbiological Culture Collection Center on September 18, 2024, and the deposit number is CGMCC NO. 31988;

[0007] The Lactobacillus plantarum ( Levilactobacillus suantsaii ) CZ25 has the DNA sequence of SEQ ID NO. 1 in the sequence listing.

[0008] A bacterial agent, said bacterial agent comprising the Lactobacillus plantarum for promoting sauerkraut growth ( Levilactobacillus suantsaii ) CZ25.

[0009] Furthermore, the viable count of Lactobacillus plantarum for promoting sauerkraut growth ( Levilactobacillus suantsaii ) CZ25 in the bacterial agent is (1.89 ± 0.45) × 10 9 CFU / mL.

[0010] Furthermore, the acid tolerance pH is 3.34 - 3.41.

[0011] The preparation method of the above bacterial agent is as follows: Inoculate Lactobacillus plantarum CZ25 into MRS medium and culture at 37°C for 24 h; inoculate the cultured bacterial liquid into the fermentation medium at an inoculation amount of 3 - 5% and culture in an incubator at 37°C for 24 h to obtain the Lactobacillus plantarum for promoting sauerkraut growth ( Levilactobacillus suantsaii ) CZ25 bacterial agent.

[0012] Furthermore, the fermentation medium: glucose 15.00 g / L, lactose 10.00 g / L, soy peptone 25.00 g / L, K2HPO4 2.29 g / L, and MgSO4·7H2O 0.80 g / L.

[0013] Furthermore, the application of the Lactobacillus plantarum for promoting sauerkraut growth ( Levilactobacillus suantsaii ) CZ25 or the bacterial agent in food production.

[0014] Compared with the prior art, the beneficial effects of the present invention are: Lactobacillus plantarum CZ25 has the effect of inhibiting harmful bacteria, its fermentation broth has the characteristic of inhibiting the growth of harmful microorganisms, can regulate the hurdle factors, and the pH value of the lactic acid solution is 3.34 - 3.41. Lactobacillus plantarum CZ25 can survive and reproduce in an environment with a relatively low pH value, has good acid tolerance and a high survival amount, can significantly extend the shelf life of food, and the sensory score and various texture indexes of the food all show good performance. Description of the Drawings

[0015] Figure 1 It is the plate colony morphology diagram of Lactobacillus plantarum CZ25;

[0016] Figure 2 It is the Gram staining microscope diagram of Lactobacillus plantarum CZ25;

[0017] Figure 3 It is the phylogenetic tree constructed by the 16S rDNA sequence of Lactobacillus plantarum CZ25;

[0018] Figure 4The bacteriostatic circle effect diagram of Lactobacillus plantarum CZ25 promoting sauerkraut in Escherichia coli;

[0019] Figure 5 The bacteriostatic circle effect diagram of Lactobacillus plantarum CZ25 promoting sauerkraut in Bacillus subtilis;

[0020] Figure 6 The bacteriostatic circle effect diagram of Lactobacillus plantarum CZ25 promoting sauerkraut in Staphylococcus aureus;

[0021] Figure 7 The comparative diagram of the bacteriostatic effect of the lactic acid solution added with Lactobacillus plantarum CZ25 promoting sauerkraut in soft pre-packaged meatballs. Detailed implementation mode

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0023] Please refer to Figures 1 - 7 , the present invention provides a Lactobacillus plantarum CZ25 promoting sauerkraut, which is isolated from pickled vegetables. The collection time is May 2024, and the collection place is Mianyang City, Sichuan Province, China. Lactobacillus plantarum ( Levilactobacillus suantsaii ) CZ25 was deposited in the General Microbiology Center of the China Committee for Culture Collection of Microorganisms on September 18, 2024, and its deposit number is: CGMCC NO.31988.

[0024] Example 1: Isolation, purification and identification of Lactobacillus plantarum CZ25 promoting sauerkraut

[0025] 1. Isolation and purification of strains

[0026] Lactobacillus plantarum CZ25 that promotes growth was isolated from pickled vegetables. The isolation and purification method is as follows: Select pickled vegetables as the raw material, take a small amount of pickled vegetable juice and add it to MRS liquid medium containing antibiotics, and culture for 24 h. After the culture is completed, add sterilized calcium carbonate to the MRS liquid medium in an amount of 2%, cool the medium to about 46 °C in a constant temperature water bath, shake it while cooling to mix the calcium carbonate evenly, and pay attention not to generate bubbles. After mixing, mix the MRS liquid medium containing 2% calcium carbonate with an appropriate amount of agar, heat it until the agar is completely dissolved, and then immediately pour it into a petri dish and let it stand and solidify to obtain MRS solid medium. Under sterile conditions, pipette 200 μL of the sample and spread it on the surface of the solidified MRS solid medium plate, and culture it in an inverted position at a constant temperature of 37 °C. Observe the colony characteristics after culturing for 24 - 48 h, pick the single colony with a large calcium dissolving circle, streak culture on the MRS solid medium to obtain a single colony strain, and streak and separate on the plate and purify repeatedly.

[0027] MRS liquid medium: Peptone 10.0 g, Beef extract 10.0 g, Yeast extract 5.0 g, Glucose 20.0 g, Diammonium citrate 2.0 g, Sodium acetate 5.0 g, MgSO4 2.0 g, MnSO4 0.05 g, K2HPO4 2.0 g, Tween 80 1.0 mL; Distilled water 1000 mL; Adjust the pH to 6.2 - 6.4, culture temperature 37 °C, culture time 16 h.

[0028] 2. Preliminary identification of colonies

[0029] Hydrogen peroxide catalase test: Use an inoculation loop to pick 1 loop of the isolated and purified colony onto a clean glass slide, and drop 1 drop of 30% hydrogen peroxide. If there are bubbles, it is catalase positive, otherwise it is negative.

[0030] Gram staining: Pick the isolated and purified colony for Gram staining and observe it under a microscope. The results of the hydrogen peroxide catalase test and Gram staining of the lactic acid bacteria after isolation and purification are shown in the following table:

[0031] Number Hydrogen peroxide catalase (±) Gram staining (G±) Microscopic examination result CZ25 - G+ Rod-shaped, existing singly or in pairs

[0032] Conclusion: As can be seen from the above table, the strain is negative for hydrogen peroxide catalase, positive for Gram staining, and rod-shaped. This strain is labeled as CZ25.

[0033] 3. Physiological and biochemical tests

[0034] Select different types of sugars to replace glucose as the carbon source to prepare MRS liquid medium. Pipette the liquid medium into a 96-well plate to measure its OD600. Inoculate CZ25 into the MRS liquid medium with different carbon sources at an inoculation amount of 1%, and culture it at 37°C for 24 h. Pipette the bacterial solution into a 96-well plate to measure its OD600. Based on "Bergey's Manual of Systematic Bacteriology" and "Classification, Identification and Experimental Methods of Lactic Acid Bacteria", conduct physiological and biochemical identification of the strain. A positive reaction result is indicated by (+), and a negative result is indicated by (-), so as to make a preliminary identification of the genus and species of the target strain. The results are shown in the following table:

[0035] Test item CZ25 Sorbitol + Mannitol + Arabinose + Lactose - Cellobiose - Raffinose - Trehalose - Ribose + Melezitose -

[0036] Conclusion: According to "Bergey's Manual of Systematic Bacteriology" and "Classification, Identification and Experimental Methods of Lactic Acid Bacteria", the target strain CZ25 was preliminarily identified as the genus Lactobacillus promoting growth.

[0037] 4. 16S rDNA sequence analysis

[0038] Use a bacterial genomic DNA extraction kit to extract the genomic DNA of the target strain. Using the genomic DNA of the target strain as a template, select 27F and 1492R as universal primers for PCR amplification of 16S rDNA. PCR reaction system (25 μL): 1 μL each of the upstream and downstream primers and genomic template, 12.5 μL of Pre-mix Ex Taq, and 9.5 μL of sterilized ddH2O. PCR amplification conditions: pre-denaturation at 95°C for 4 min, denaturation at 94°C for 1 min, annealing at 58°C for 1 min, extension at 72°C for 2 min, a total of 30 cycles, and finally extension at 72°C for 7 min to end the reaction. The PCR product is sent to BGI Tech Solutions Co., Ltd. for purification and sequencing. The obtained PCR product sequence and the 16S rDNA sequences of lactic acid bacteria with relatively close genetic relationships are used to construct a phylogenetic tree by MEGA 5.05 software. The phylogenetic tree is as shown in the appendix Figure 3 shown

[0039] The sequencing result is:

[0040] GGGGGGGGCCTGACGTATTGACCTGAGGCTCGAGGGTGGGTAGCGAACGGGATTAGATACCCTGGTAGTCCATGCCGTAACGATGAGTGCTAAGAGGTGGAGGGTTTCCGCCCTTCATTGCTGAAGTTAACGCATTAAGCACTCCGCCGGGGAAGACCGACCGCAAGGTTGAAATTCAAAGGAATTGACGGGGGCCCGCACAAGGGGGGAAGATTGGGGTTTAATTCAATGCTACGCAAAAAACCTTACCGGGCCTTGACTTCTTCTGACTTTCTAAAAAAGTATGGGTGCCCTTCGGAAACGGAATGACAGGGGTGGCTGGGTGGCCGCCAGTTCGGGTCGGGAAAGGTTGGGTTAAGCCCCGCAACAAGCGCAACCCTTATTGTTAGTTGCCAGGATTCGGTTGGGCACTCTAAGGAGACTGCCGGTGACAAACCGGAGGAAGGTGGGGATGACGTCAAATCATCATGCCCCTTATGACCTGGGCTACACACGTGCTACAATGGACGATACAACGAGACGCGAAACCGCGAGAGCAAGCTAATCTCTTAAAGCCGGTCTCAGTTCGGATTGTAGGCTGCAACTCGACTACATGAAGTTGGAATCGCTAGTAATCGTGGATCAGAATGCCACGGTGAATACGTTCCCGGGCCTTGTACACACCGCCCGTCACACCATGAGAGTGTGTAGCACCCGAAGCCGGTGAGGTAACCTTCGGGGGACCAGCCGACCAATTTGTGACAGATGATTGGGGTGAAGC

[0041] The target strain CZ25 was identified as Lactobacillus plantarum for promoting sauerkraut growth according to the sequencing results ( Levilactobacillus suantsaii ).

[0042] Example 2: Changes in the pH value of the culture solution during the fermentation of Lactobacillus plantarum CZ25 for promoting sauerkraut growth, and determination of the fermentation time of CZ25

[0043] Inoculate Lactobacillus plantarum CZ25, which promotes the growth of pickled vegetables, into MRS medium and culture it at 37 °C for 24 h; inoculate the cultured bacterial liquid into the fermentation medium at an inoculation amount of 3-5% (volume ratio) and place it in an incubator at 37 °C for culture.

[0044] MRS medium: 10 g peptone, 5 g beef powder, 4 g yeast powder, 2 g glucose, 1 mL Tween 80, 2 g dipotassium hydrogen phosphate, 5 g sodium acetate, 2 g ammonium citrate, 0.2 g magnesium sulfate, 0.05 g manganese sulfate, 20 g calcium carbonate, 1000 mL distilled water.

[0045] Fermentation medium: 15.00 g / L glucose, 10.00 g / L lactose, 25.00 g / L soy peptone, 2.29 g / L K2HPO4, 0.80 g / L MgSO4·7H2O.

[0046] Preparation methods of MRS medium and fermentation medium: Add the formula components into distilled water according to the ratio, heat and dissolve, and autoclave at 121 °C for 15 minutes.

[0047] The changes in the pH value of the culture solution during the fermentation of Lactobacillus plantarum CZ25, which promotes the growth of pickled vegetables, are shown in the following table:

[0048] Fermentation culture time (h) pH value 0 6.66 12 4.28 18 3.86 24 3.41 30 3.34

[0049] Conclusion: Lactobacillus plantarum CZ25, which promotes the growth of pickled vegetables, can reduce the pH value of the fermentation broth during fermentation and growth. The pH value continuously decreases with the prolongation of the fermentation time. At the beginning, the pH decreases rapidly and then slowly decreases and tends to be stable after 18 h. It can be seen from this experiment that Lactobacillus plantarum CZ25, which promotes the growth of pickled vegetables, can survive and reproduce in an environment with a relatively low pH value, reflecting the acid resistance of Lactobacillus plantarum CZ25, which promotes the growth of pickled vegetables. The pH value of the fermentation broth remains basically unchanged after 24 h and 30 h of fermentation. Select 24 h as the fermentation time of Lactobacillus plantarum CZ25, which promotes the growth of pickled vegetables.

[0050] Example 3. Determination of the viable count in the fermentation broth of Lactobacillus plantarum CZ25, which promotes the growth of pickled vegetables

[0051] The viable count is determined by the plate coating method. Prepare MRS agar medium, autoclave it at 121 °C for 15 min, and pour the plate after the medium cools to 48 °C. Pour about 15-20 mL of MRS medium into each petri dish. Take samples for gradient dilution. Pipette 1 mL of the bacterial liquid into a test tube containing 9 mL of sterile normal saline, and dilute the sample to 10 -1 , and repeat the operation for gradient dilution to 10 -7 . Pipette 200 μl of 10 -5 , 10 -6 , 10 -7Dilute the bacterial suspension on the solidified MRS agar medium, spread it evenly with a sterile spreading rod, and incubate it upside down in a constant temperature incubator at 37°C for 24 h before counting. The results showed that the viable count of the fermentation broth of Lactobacillus plantarum CZ25 promoting sauerkraut was (1.89 ± 0.45) × 10 9 CFU / mL.

[0052] Example 4: Determination of the antibacterial effect in the fermentation broth of Lactobacillus plantarum CZ25 promoting sauerkraut

[0053] The bacteriocin was determined by the Oxford cup double-layer agar diffusion method. Take the test sample, centrifuge it at 4000 r / min for 3 min, and take the supernatant. Using Escherichia coli, Bacillus subtilis, and Staphylococcus aureus as indicator bacteria, take 200 μL of the supernatant and place it in the Oxford cup. The diameter of the Oxford cup is 8.0 mm, and it is cultured in an incubator at 37°C for 24 - 48 h. Observe the inhibition zone, measure and record the diameter of the inhibition zone. The results are shown in the following table and appendix Figures 4 - 6 as follows:

[0054] Indicator bacteria Inhibition zone diameter (mm) Escherichia coli 14.05±0.15 Bacillus subtilis 16.00±0.70 Staphylococcus aureus 11.15±0.15

[0055] Conclusion: Lactobacillus plantarum CZ25 promoting sauerkraut has an inhibitory effect on the growth of Escherichia coli, Bacillus subtilis, and Staphylococcus aureus. Among them, the inhibitory effect on Bacillus subtilis is the best, and the diameter of the inhibition zone can reach 16.00 mm; the inhibitory effect on Escherichia coli is the second, and the average diameter of the inhibition zone is 14.05 mm; when Staphylococcus aureus is used as the indicator bacteria, the average diameter of the inhibition zone is 11.15 mm. Lactobacillus plantarum CZ25 promoting sauerkraut has an obvious inhibitory effect on common pathogenic bacteria.

[0056] Example 5: Effects of adding the fermentation broth of Lactobacillus plantarum CZ25 promoting sauerkraut on the quality (hardness, elasticity, cohesiveness, chewiness, and taste, etc.) of soft pre-packaged meatballs

[0057] Inoculate the activated Lactobacillus plantarum CZ25 promoting sauerkraut at an inoculation amount of 3% by mass ratio and ferment it at 37°C for 12 h to obtain the fermentation broth.

[0058] Under the condition that other raw materials and the meatball processing technology remain unchanged, divide the experimental groups into experimental group one (the fermentation broth and the sample are added according to the ratio of 0:100), experimental group two (the fermentation broth and the sample are added according to the ratio of 4:100), experimental group three (the fermentation broth and the sample are added according to the ratio of 8:100), and experimental group four (the fermentation broth and the sample are added according to the ratio of 12:100). The above ratios are all mass ratios.

[0059] Each group conducted 5 parallel tests to detect the quality hardness, elasticity, cohesiveness, chewiness, and taste of the soft pre-packaged meatballs. Among them, hardness, elasticity, cohesiveness, and chewiness were texture indicators, which were measured by the texture profile analysis (TPA) method. Taste was a sensory indicator, and its scoring criteria were as follows: excellent was 5 points, average was 3 points, and poor was 1 point.

[0060] The effects of adding the fermentation broth of Lactobacillus plantarum CZ25 promoting growth with pickled Chinese cabbage on the quality of soft pre-packaged meatballs are shown in the following table:

[0061] Group Hardness / g Elasticity Cohesiveness Chewiness Taste Test Group 1 2127.18±19.34 0.52±0.001 0.42±0.001 527.51±1.84 3 Test Group 2 2155.27±14,76 0.53±0.001 0.42±0.001 510.95±4.05 5 Test Group 3 2068.62±18.64 0.53±0.001 0.42±0.001 505.29±3.57 5 Test Group 4 1794.37±36.25* 0.51±0.001 0.40±0.001 456.89±3.92* 3

[0062] Note: Compared with experimental group 1, *P<0.05

[0063] With the increase in the addition amount of the fermentation broth of Lactobacillus plantarum CZ25 promoting growth with pickled Chinese cabbage, the changes in the hardness and chewiness of the meatballs were significant (P<0.05); the changes in the elasticity and cohesiveness of the meatballs were not obvious (P>0.05); when the addition amount of the fermentation broth of Lactobacillus plantarum CZ25 promoting growth with pickled Chinese cabbage reached 8:100, the sensory scores and various texture indicators of the meatballs were all good. After adding an appropriate amount of the fermentation broth of Lactobacillus plantarum CZ25 promoting growth with pickled Chinese cabbage, the taste was improved. On the premise of ensuring that the addition of the fermentation broth of Lactobacillus plantarum CZ25 promoting growth with pickled Chinese cabbage does not affect the quality of the soft pre-packaged meatballs, the maximum addition amount of the fermentation broth of Lactobacillus plantarum CZ25 promoting growth with pickled Chinese cabbage is 8:100.

[0064] Example 6. Effects of adding the fermentation broth of Lactobacillus plantarum CZ25 promoting growth with pickled Chinese cabbage on the shelf life of soft pre-packaged meatballs

[0065] The activated Lactobacillus plantarum CZ25 was inoculated at an inoculation amount of 3% by mass ratio and fermented at 37 °C for 12 h to obtain the fermentation broth.

[0066] Experimental purpose: To test the antibacterial, bactericidal, antiseptic, and fresh-keeping effects of the fermentation broth of Lactobacillus plantarum CZ25 added to soft pre-packaged meatballs.

[0067] Experimental conditions: From August 15, 2024 to October 17, 2024 in Weifang, Shandong, at a constant temperature of 18 °C - 38 °C throughout the day.

[0068] Groups: Conventional preservative group (adding nisin, addition amount is 500 mg / kg);

[0069] Experimental group (adding the fermentation broth of Lactobacillus plantarum CZ25 fermented for 12 h, and the fermentation broth and the sample are added according to a mass ratio of 6:100).

[0070] The conventional preservative group and the test group were each conducted 5 parallel tests. The appearance of the soft pre-packaged meatballs was detected every 10 days. Staphylococcus aureus was detected in accordance with GB 4789.10, Salmonella was detected in accordance with GB 4789.4, and Escherichia coli was detected in accordance with GB 4789.3. The two samples were compared as shown in the following table and Figure 7 as follows:

[0071] Group Day 10 Day 20 Day 30 Day 40 Day 50 Day 60 Conventional preservative group Normal Staphylococcus aureus detected Staphylococcus aureus detected Staphylococcus aureus detected, and juice oozed out with browning Staphylococcus aureus detected, and juice oozed out with browning Staphylococcus aureus detected, and juice oozed out with browning Test group Normal Normal Normal Normal Normal Staphylococcus aureus detected

[0072] In summary, it shows that the test group of meatballs added with the fermentation broth of Lactobacillus plantarum CZ25 promoting sauerkraut has significantly better effect in inhibiting Staphylococcus aureus than the conventional preservation method, and significantly extends the shelf life of the meatballs, up to 5 times.

[0073] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes. However, any simple modifications, equivalent changes and modifications made to the above examples based on the technical essence of the present invention without departing from the technical solution content of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A sauerkraut growth-promoting lactobacillus ( Levilactobacillus suantsaii )CZ25, characterized by: The sauerkraut growth-promoting Lactobacillus ( Levilactobacillus suantsaii )CZ25 was deposited in the General Microbiology Center of China Microbiological Culture Collection Administration on September 18, 2024, with the deposit number CGMCC NO.31988; The sauerkraut growth-promoting Lactobacillus ( Levilactobacillus suantsaii ) CZ25 has the DNA sequence of SEQ ID NO.1 in the sequence listing.

2. A bacterial agent, characterized in that: The bacterial agent comprises the sauerkraut growth-promoting Lactobacillus ( Levilactobacillus suantsaii )CZ25.

3. A bacterial agent according to claim 2, characterized in that: The bacterial agent contains sauerkraut growth-promoting lactobacillus ( Levilactobacillus suantsaii ) The viable count of CZ25 was (1.89±0.45)×10 9 CFU / mL.

4. The bacterial agent according to claim 2, characterized in that: Acid resistance pH is 3.34-3.

41.

5. The bacterial agent according to claim 2, characterized in that: The bacterial agent is prepared according to the following method: The sauerkraut growth-promoting Lactobacillus CZ25 was inoculated into MRS medium and cultured at 37°C for 24 hours; the bacterial liquid obtained after the culture was inoculated into the fermentation medium at an inoculum rate of 3-5%, and cultured in a 37°C incubator for 24 hours to obtain the sauerkraut growth-promoting Lactobacillus ( Levilactobacillus suantsaii )CZ25 bacterial agent.

6. The bacterial agent according to claim 5, characterized in that: Fermentation medium: glucose 15.00 g / L, lactose 10.00 g / L, soy peptone 25.00 g / L, K2HPO4 2.29 g / L and MgSO4·7H2O 0.80 g / L.

7. The sauerkraut growth-promoting Lactobacillus according to claim 1 ( Levilactobacillus suantsaii ) Use of the bacterial agent described in CZ25 or claim 2 in food production.

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